Is It Illegal to Operate a Boat While Under the Influence?

All states have laws that prohibit operating a boat or other watercraft while under the influence of drugs or alcohol. States use various names for the offense such as "boating under the influence" (BUI), "boating while intoxicated" (BWI). State laws also vary somewhat in how they define boating under the influence. Here are some of the basics on boating-under-the-influence regulations.

What Qualifies as Boating Under the Influence?

State BUI laws vary in two main respects: the types of watercraft they apply to and how they define being "under the influence."

Boats and Watercraft Subject to BUI Laws

In most states, a boater can be arrested for a BUI only while operating a boat that's powered by a motor. In these states, BUI restrictions apply to motorboats and jet skis but not to rowboats, sailboats (without motors), and the like.

However, a few states have BUI laws that are broader and apply to most types of watercraft, regardless of whether powered by a motor. In some states, you can even be prosecuted for a BUI for waterskiing while under the influence.

How "Under the Influence" Is Defined

In most states, the BUI laws define "under the influence" the same ways as the state's DUI laws do. So, a boater can generally be convicted of a BUI for operating a vessel:

• with a blood alcohol concentration (BAC) of .08% or more (in a few states the BAC level is different), or
• while impaired by drugs or alcohol.

In other words, a BUI can be based on BAC or actual impairment. However, the level of impairment that meets this standard also varies by state. For example, some states require proof that the boater was substantially impaired, while any impairment at all is enough to be convicted of a BUI in some other states.

How Can You Fight a BUI Charge?

If you get arrested for boating under the influence, it's a good idea to talk to an experienced DUI attorney. Typically, lawyers don't specialize in BUI cases. But the laws and defenses for both types of cases (BUIs and DUIs) are very similar. So, an experienced DUI attorney is your best bet for fighting a BUI charge.

In many cases, fighting a BUI charge involves challenging the reliability of the blood or breath test results the prosecution is relying on to prove your BAC level. Depending on the situation, there might also be a dispute on whether the boater was actually operating the boat while impaired. Generally, a boater can't be convicted of a BUI if the boat is anchored or tied up.